The Peribonka River is a river emptying in Sainte-Monique, in Lac-Saint-Jean-Est Regional County Municipality, in the Saguenay-Lac-Saint-Jean area in Quebec, Canada. It is 451 kilometres (280 mi) long and drains an area of 28,200 square kilometres (10,900 sq mi). It drains into Lac Saint-Jean at Pointe-Taillon National Park and is the largest tributary of this lake. The town of Péribonka is located on the north shore of Lac St-Jean at the river's mouth.

Lac Saint-Jean is a large, relatively shallow lake in south-central Quebec, Canada, in the Laurentian Highlands. It is situated 206 km (128 mi) north of the Saint Lawrence River, into which it drains via the Saguenay River. It covers an area of 1,053 km2 (407 sq mi), and is 63.1 m (207 ft) at its deepest point. Its name in the Innu language is Piekuakamu.